Opportunistic human viruses and their simian counterparts are similar in their genetic makeup and induce a similar spectrum of diseases in their immunosuppressed hosts. Experimental lentivirus infections in rhesus macaques are widely recognized as the most import animal model for AIDS-related research and there is an urgent need to expand breeding programs to meet future AIDS vaccine and pathogenesis research program needs. Development of an Indian rhesus macaque breeding colony free of opportunistic viral agents is proposed to enhance the usefulness of this unique resource for studies focused on AIDS-related opportunistic infections. Housing space is proposed to provide a protected environment for this unique Expanded Specific Pathogen Free (ESPF) macaque resource and to facilitate enhanced macaque breeding efforts.